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arXiv · hep-ph/0606267

Transition from real to virtual polarized photon structures

T. Ueda·T. Uematsu·K. Sasaki
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Abstract

We investigate the transition of the polarized photon structure function $g_1^γ(x,Q^2,P^2)$ when the target photon shifts from on-shell ($P^2=0$) to far off-shell ($P^2\gg Λ^2$) region. The analysis is performed to the next-to-leading order in QCD. The first moment of $g_1^γ$ which vanishes for the real photon, turns to be a negative value when target photon becomes off-shell. The explicit $P^2$-dependence of the first moment sum rule as well as of the structure function $g_1^γ(x,Q^2,P^2)$ as a function of $x$ is studied in the framework of the vector meson dominance model.

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T. Ueda, T. Uematsu, K. Sasaki. 2006-06-26. Transition from real to virtual polarized photon structures. https://doi.org/10.1016/j.physletb.2006.07.068

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